1.5.1.5 Linux Shared Folders

in a mixed windows-linux system, the necessity to have a common storage between the OS could arise. This is given on linux side by SAMBA software to let it use the smb:// protocol, the same protocol that windows use to create shared folders.

install samba package on the linux server hosting the folder you want to share

sudo apt install samba -y

and edit its configuration file /etc/samba/smb.conf as follows

$ sudo nano /etc/samba/smb.conf

place the following configuration on the bottom of the file. This is a shared folder configuration example, modify it according to your needs if necessary:

[$SHARE_NAME]                                       #name of the shared folder 

   comment = My Test Directory                #comment, skippable

   path = /home/my_directory                                  #local path where the shared folder points

   browseable = yes                                   

   read only = no

   guest ok = yes               #allows guest login. change with "valid users" if you want restricted access

   writable = yes

   create mask = 0775                     # permissions that new files will have inside the shared folder

   directory mask = 0775                 # permissions that new directories will have inside the shared folder

   force user = $MY_USER                # force samba to use a specific user for the operations

   force group = $MY_USER             # force samba to use a specific group for the operations

samba have its own users database. If you need to access a shared folder from outside the hosting server with a specific user, you can populate its database with existing users:

sudo smbpasswd -a your_username         #sets a samba password for your_username

note: if the user have already a samba password, it will simply rewrite it

Samba have its own identification layer, but you can also manage folder permissions on server side

sudo chmod 777 /home/my_directory

in this way you can decide which one can have remote access to the folder, and which one can have access to that folder only locally

to test the smb.conf synthax without executing it

testparm /etc/samba/smb.conf

note: after every new settings, restart samba service

sudo systemctl restart smbd nmbd

the following instructions will describe how to access a shared folder from each OS (they're valid to access both windows and linux shared folders)

Access the shared folder from Windows

you can access to the shared folder from windows file explorer with path \\ip.of.the.server\folder but, for linux shared folders, windows policies could prevent you from accessing it (at least for guest login) and file explorer wouldn't be able to find the path.

In that case, from cmd or powershell (open it as administrator if you want to access the folder with administrator software):

net use X: \\ip.of.the.server\folder /user: your_user 'password'

this will map the shared folder to X:\ , now it is accessible from File Explorer (if you have run it as administrator you'll need to open file explorer as administrator)

Access the shared folder from Linux

to access the folder from the terminal you have two options

smbclient            # SMB shell client

cifs-utils              # Tools to mount the drive locally

smbclient

install it:
sudo apt install smbclient -y

then you can already connect with:
smbclient //IP_ADDRESS/SHARE_NAME -U YOUR_USERNAME

ex: sudo smbclient //dc1/data -U jdoe@vmmaurlx01

it behaves like an FTP client, common commands are:

ls or dir                                               # list files and folders

cd                                                       # enter the directory

pwd                                                    # print the current working directory path on the remote share

get                                                     # download a file

mget                                                  # download a set of files matching a wildcard (ex mget *.pdf)

put                                                     # upload a file

mput                                                  # upload a set of files matching a wildcard (ex mput *.pdf)

mkdir                                                 # create a directory

rmdir                                                 # delete a directory

rm                                                     # delete a file

rename <oldname> <newname>   # rename a file

lcd <local_directory>                       # change your local directory without disconnecting from the share

! <command>                                 # run any standard linux command on local machine without disconnecting

cifs-utils

this is a set of tools that lets the user to mount, manage and interact with network file systems using the SMB/CIFS protocol.

To mount temporarily from command line

sudo mount -t cifs //server/share /mnt/mountpoint -o username=user,password=pass,vers=3.0

make sure that the mount directory exists by creating it : sudo mkdir -p /mnt/mountpoint

note: "vers" refers to smb protocol version. It is mandatory that the SMB versions of the shared folder and the one declared match, otherwise the connection will fail

to mount the volume permanently you can edit /etc/fstab

sudo nano /etc/fstab

add this line example on the bottom. adjust it accordingly to your mount point you set before

//172.31.230.110/data  /mnt/asusw1102ub_data  cifs  credentials=/etc/samba/smb_data.cred,vers=3.1.1,uid=1000,gid=1000,iocharset=utf8,_netdev,nofail,x-gvfs-show  0  0

now you can reboot the workstation or 

sudo mount -a

and access the shared folder through /mnt/asusw1102ub_data or any mount point you've chosen